The „credit” or the “blaming” or the responsibility – depending on the point of view one takes - to be the initiator of the Crusades belongs to Pope Urban II (1088 to1099). He was born a noble man in France at Lagery (near Châtillon-sur-Marne) and was church-educated.
Also he was known as one of the most prominent and active supporters of the Gregorian reforms and probably the ablest of the so-called reforming popes of the 11th and 12th century, and finally Odo of Lagery was elected Pope Urban II (March 1088). By taking up the policy of Pope Gregory VII, Urban showed greater flexibility and diplomatic finesse. Although he had to deal with the presence of the powerful antipope Clement III (1080 and1084-1100) he started a kind of a renewal of the Church and made declarations against simony, lay investiture, and clerical marriages. On the Council of Clermont, which was a mixed synod of ecclesiastics and laymen of the Catholic Church, held from November 18th to November 28th Urban discussed several reforms and other issues of the Church.
Finally on November 27th at this council he delivered the famous address which led thousands of knights an ordinary people to take the cross and march to the East.
Several versions of this famous speech have come to us but it cannot be proved that any of the authors were present at the Council of Clermont. So these different versions of the speech do not inevitably reflect the true speech held by Urban but the reflections of the speech and the following events by the author and his believing.
The most important and most cited versions of the speech are the one of Fulcher of Chartres, Baldric of Dol, Robert the Monk, Guibert of Nogent and the version of the Gesta Francorum by an anonymous author.
But before going into the speeches it might be helpful to sketch the historical background of this speech.
The appeal of Urban II was made at a time of political, military and religious changing in Europe and in the East. Only some twenty years ago an almost similar call of Pope Gregory VII was largely ignored, but it focused the attention more to the East, to the Eastern Church, the Byzantine Empire and last not least to Jerusalem, the Holy City.
In Europe of the 11th and 12th century pilgrimage increased, and so information the knowledge about the East increased as well. Also we have to consider the so-called Cluniac Reform (started in the 11th century), which restored the moral and therefore the authority of the church after centuries of corruption and decadence.
And because of his noble birth into the French aristocracy Odo-Urban before his papacy already had close contact to the French aristocracy, and therefore he was also well informed about their needs and problems. After centuries of expansion the Carolingian Empire crushed down, but still the class of warriors exists, now turning their violence and military efforts inwards to their neighbors. Because political power in France had fragmented and the king no longer implemented control over the provinces the dukes and counts now governed these provinces.
The Church also was inflicted on this violence, so it had taken the leadership of a movement of Peace and Trust of God. Already before his acclamation Odo-Urban was in touch with the movement of Pax Dei and Treuga Dei (often called as Peace and Truce of God movement) which was developed in France in the 10th century and applied spiritual sanctions in order to control and stop the violence of feudal society in France and Europe. So the people lived and traveled and fought under the protection of God and the Church, which was a main point later on in the idea of the Crusades as an armed pilgrimage to the Holy Land. Surely this idea of “under the protection of God and the church” was in Urban´s mind when he called for the Crusade.
 E.Peters (Ed.). The first crusade. The chronicle of Fulcher of Chartres and other source materials. Second edition. Philadelphia 1998. p.25
 To the versions of Fulcher of Chartres, Robert the Monk, Baldric of Dol, Guibert of Nogent and William of Malmesbury see D.Munro. The speech of Pope Urban II at Clermont, 1095. in: AHR 11.2 (1906) pp.231-242
 Historia Iherosolymitana … auctore domno Fulcheri Carnotensi, RHC Occ. 3. 311-485.
 K.Sidwell, RML. 222-223 and Baldrici episcopi Dolensis Historia Jerosolimitana, RHC Occ. 4. 1-111.
 Roberti Monachi historia Iherosolimitana, RHC Occ. 3. 717-882
 Guibert of Nogent, Historia quae dicitur Gesta Dei per Francos, RHC Occ. 4. 113-263
 R.Hill. Gesta Francorum et aliorum Hierosolimitanorum. London 1962
 Mainly because of the problems with the lay investiture, the fight of the German king Henry IV against the Saxons, the unsolved problems with the Normans in Sicily, the interior struggles in the Byzantine Empire and the difficult communication between both churches, but also personal failings of Gregory VII and his non-French origin
 Monumenta Germaniae Historica, Schriften, Band XIX/2. Alfons Becker, Papst Urban II. (1088-1099), Teil 2: Der Papst, die griechische Christenheit und der Kreuzzug, Stuttgart 1988. p.274
 J.Riley-Smith. The First Crusade and the idea of crusading. London 1986. p.3
 Monumenta Germaniae Historica, Schriften, Band XIX/2. Alfons Becker, Papst Urban II. (1088-1099), Teil 2: Der Papst, die griechische Christenheit und der Kreuzzug, Stuttgart 1988. p.275
 Monumenta Germaniae Historica, Schriften, Band XIX/2. Alfons Becker, Papst Urban II. (1088-1099), Teil 2: Der Papst, die griechische Christenheit und der Kreuzzug, Stuttgart 1988. pp.276-279